Histopathological Characteristics of Lymphomas in the Upper Aerodigestive Tract. A Single-Institute Study in Japan.

We analyzed the histopathological characteristics of lymphomas biopsied from the upper aerodigestive tract between 2000 and 2014 at the National Cancer Center Hospital in Japan. Of a total of 309 consecutive cases, the following incidences were observed: mature B-cell neoplasms, 77% (n = 239); mature T- and NK-cell neoplasms, 20% (n = 63); classical Hodgkin lymphomas, 0.7% (n = 2); and lymphoblastic lymphomas, 2% (n = 5). Lymphomas were most frequently (57%) detected in the oropharynx. The majority of cases (89%) were mature B-cell neoplasms (diffuse large B-cell lymphoma, 60%; follicular lymphoma, 10%), and 10% of cases were mature T-cell neoplasms. Six cases of plasma cell neoplasm (4 primary and 2 secondary involvement) and 2 cases of plasmablastic lymphoma in the upper aerodigestive tract were observed. Two out of 3 cases of extraosseous plasmacytoma with available biopsy material were positive for EBER1. All 3 patients received irradiation and achieved complete response; 1 had not relapsed after 17 months and the remaining 2 relapsed as plasma cell myeloma and solitary plasmacytoma of the bone. Of 47 extranodal NK/T-cell lymphoma, nasal-type cases in the upper aerodigestive tract, 38 (81%) were present in the sinonasal region and the remaining 9 (19%) were in the oropharynx (n = 4), nasopharynx (n = 3), and oral cavity (n = 2). In conclusion, since both primary lymphoma and secondary involvement of lymphoma are often diagnosed using biopsied materials from the upper aerodigestive tract, pathologists and hematologists should recognize the characteristics of lymphoma in this tissue.